Fluid-pressure motor.



G. W. BURNHART.

FLUID PRESSURE MOTOR. APPLICATION FILED APR.21.1913.

1,142,551. Patented June 8,1915.

in I I GEORGE WfBURNI-IART, or D E Nvna ooLoRAnoY FLUID-PRESSURE MOTOR.

To all whom may concern Be it known that I, GEORGE W. BURNHART,

a citizen of the United States residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Fluid-Pressure Mo- I tors, of which the following is a specification. v

This invention relates to fluid pressure motors and my object is to provide a motor adapted for various duties and for use in connection with compressed air, gas, steam or other fluids under pressure.

More particularly the invention contem-' plates a piston cyllnder form of engine in which various peculiar and novel features of piston and valve construction are, 1n-

volved to be hereinafter referred to, and a special feature will be noted as residing in an arrangement of valve and valve-tripping means whereby the stroke of the piston may be regulated. 1 Y v With these general objects in view my in-,

vention comprises details of construction as my motor is provided with cylinder heads 2 and iclamped to the cylinder body casing 6, by means of tie bolts 7/ For supplying fluid pressure to the cylinderfi, an inlet opening to the latter is provided through a threaded pipe 8;, the connection with the cylinder being sealed by packing lO secured tightly in place by a nut 12. Opposite the inlet opening is provided an outlet open ng through pipe .14, the same tight 'connectionbeing madeby a nut 12 and packing 1.0

Sliding within the cylinder 6, is aplston 16, which is approximately X-shape in cross section as shown in Fig. 2. The upper half of the piston is provided "with a receiving pocket 18 in communication with the inlet opening through pipe 8 and also communicating through a passage 20 w1th the valve tube 22 slidingly carried within the lower half of the piston, which lower half is also provided with a discharge pocket 24: in communication with the outlet opening through the pipe 14;. The said pockets 18 and 24 are Specification of Letters Patent.

Y within the tube '22.

V shut ofi from communication with the rest a 4 atented June 8, 19 15. Application filed A ril 21, 1913. seriailvoflea m r of, the cylinder at their ends by the heads of the piston and the parts ofthepiston in contact. with the cylinder are fitted with packings 26. The piston rod 28 istapped 'for engagementiwith the body. of the piston between t p s'ls and 24 and slides through the head 2, this passageway being Vmade tight by a collar-30 and pa'cking'32.

The cylinder may be drained when n'ecessary through the pet-cocks 34 providedfin connection with thecasing 6. The valve tube 22is provided with a series ofv inlet r ports 36, formed through its middle portion for communication with the pocket 38 provided' in the piston at the lower end of the passage 20. These ports also have com- 7 munication alternately with'opposite ends of the cylinder through the opposite ends of the tube 22, and in order to shut off communlcatlon alternately with the opposite ends of said tube, a'valve disk-40 slides back and forth through themiddle of the tube past the ports; The disk is operated by a rod 42 jconnected thereto and extending entirely through the tube and designed to abutalternately atits opposite ends against twoadjustable'stops 4A andtti threaded re spect'ively through the cylinder heads 2 and 4, and in alinement with'said rod. To each endpof the tube 22 is threaded a ring48 for closing the discharge ports 50 formed as annular passages about the endsof the tube and through the adjacent portions of piston 16, and communicating through openings 52 with thedischar-ge pocket 24. Rings 48' are operated to close andopen the ports 50 by the movementof the tube 22 at the end of each stroke of the pistojm'the tube being moved not only with the piston but relatively thereto by the disk-4:0, which is forced against the inner ends of sleeves 54 secured ,7 In Fig. 1 of the drawing, the pistoni'is shown as having been forced to the right end of' the cylinder, during which stroke the valve disk 40 was at the right of the ports- 36 'andthe'right hand port 50 was open so that the air or other fluid within the right hand end of the" cylinder was forced out through the corresponding opening 52 and outlet let. But. just as the piston was reach-' ing the end of said stroke the rod 42 met the stop 4 4 forcing the disk 40 and in turn the tube 22 into the position shown and consequently closing the right hand port 50, in

which position they are ready for the return stroke of the piston. The fluid enters the ports 36 and passes through the valve tube to the space behind the right hand end of the piston, it being noted that the opposite discharge port 50 is now open preparatory to the movement of the piston into that end of the cylinder to force its fluid contents through said port to the pipe 14. As the piston moves to the left under the force of the pressure applied to its right hand end, the rod 42 comes into contact with the stop 46 so that the continued movement of the piston closes the ports 36 by their being brought over the valve disk 40, and after the ports 36 have been closed, the piston moves slightly farther due to the momentum it has gathered accompanied by the expansion of the fluid that is behind the piston. This last movement of the piston opens the ports 36 on the other side of the valve disk 40 and the sleeve 54 meets the disk 40 whereby the valve tube 22 is drawn to the right through the piston thus closing the left hand port 50 and opening the right hand port. The parts are now put in position for the fluid to enter at the left of the piston, the next movement of which will be toward the opposite end of the cylinder from which it will force the fluid that has been used through the corresponding port 50, repeating the operations thus described. In order to obviate any tendency of the piston to rotate within the cylinder and to maintain the alinement of the rod 42 with its stops 4-4 and 46, I provide the middle portion of the piston with a guiding extension 56, the outer end of which is forked to form a .guideway for engagement with the guiding stud 58, which latter may be in the form of a set screw passed through the side of the cylinder casing 6, represented in dotted lines 'in Fig. 2, and shown in full lines in the broken away portion of the piston in Fig. 1.

This fluid pressure motor, will be found adapted to many uses, for example, for pumps in pumping water or the like, or for air compressors, etc., one special use being connection with ore concentrators and slimers, for operating the reciprocating ore tables as illustrated in my co-pending application No. 756385, filed March 24, 1913, where it is particularly desirable to employ a driving means which is not subject to any rebounding action. Since in the applicants motor the fiuid always has access to one end of the piston or the other, and the ports are instantly shifted at the end of each stroke, the piston is reversed without any rebound.

Furthermore because of this continuous access of fluid to one or the other end of the piston, the latter has no dead-center position, but may be started from any position Copies of this patent may be obtained for five cents each, by addressing the which it may happen to occupy, and, as already indicated, the stroke of the piston may be adjusted by simply regulating the position of the stops for the valve rod.

While I have illustrated onevdesired form which my invention is adapted to take, it is obvious that various changes will suggest themselves to one skilled in the art, and I reserve the right to such changes as will properly fall within the scope of the appended claim.

I claim A fluid pressure cylinder having inlet and exhaust openings at opposite sides, an X- shaped piston within the cylinder having a receiving pocket between its upper arms, in communication with the inlet opening, a passage'extending downwardly from said pocket, a circular chamber at the lower end of the passage, an exhaust pocket below the said circular chamber, in communication with the exhaust opening, a pair of end ports and a pair of exhaust openings connecting said end ports with the exhaust pocket, a piston rod connected to the piston and extending through one of the heads or ends of the cylinder, and a guiding means to prevent rotation of the piston, a valve tube extending slidingly through the piston and projecting beyond the ends thereof and also extending centrally through said circular chamber and said end ports and provided centrally with one or more perforations always in communication with the said circular chamber, external rings mounted on the extremities of the tube for alternately closing communication between the said end ports and the cylinder at opposite ends of the piston, a pair of short tubes secured to and within the perforated tube and terminating in planes at opposite sides of the perforated portion of said first-named tube, a valve fitting in the perforated tube between the short tubes and adapted to slide from one side of the perforation or perforations to the other, and a stem secured to said valve and adapted through encountering resistance alternately offered by the heads of the cylinder under travel of the piston, to slide said valve from one side of said perforation or perforations to the other and cause said valve by alternately pressing on the inner ends of said short tubes to slide the first-named tube in opposite directions alternately until its rings alternately engage the ends of the piston to close the adjacent end ports.

In testimony whereof, I afiix my signature in the presence of two witnesses,

GEORGE W. BURNHART.

Witnesses BERNARD J. FORD, ANNA E. WELSH.

Commissioner of Patents.

Washington, D. G. 

